Not necessarily, generally only Austria and Bohemia get it from being Emperor with the latter occasionally getting Inheritance without being Emperor or while having less than 8 provinces.If the Emperor is reasonably powerful (8 provinces, 6 if Austria). So yes, Bohemia isn't all that unlikely: it's a pretty powerful prince in the HRE, and it's an elector to boot, so it has all the chances to be elected. It also starts with 7 provinces, so it only needs to win one more somewhere. And that's where the difference between Bohemia and the Palatinate lies: the latter needs to get expand from 3 provinces to 8, which is why we see it a Palatinate Burgundy much less often than a Bohemian. (or at least I do.)
If emperor isn't eligible then it goes to neighbouring HRE member with royal marriage and 3+ provinces, HRE member with royal marriage and 3+ provinces, Castille/Spain not a member of HRE with royal marriage, Emperor, a neighbouring monarchy in Europe but not in the British Isles and finally a neighbouring country in Europe but not in the British Isles. All require not being subject. If none are eligible then I presume Burgundy survives only losing their french lands to France since there isn't anything further.
Sadly never saw a screenshot of a non-member of the HRE besides Castille/Spain get the inheritance.